En route to fight one of his many duels, French politician Georges Clemenceau bought a one-way train ticket. Was he pessimistic? "Not at all. I always use my opponent's return ticket for the trip back." Some Hillary Clinton advisors, although not that serene, think her victory is probable and can be assured. Her challenge is analogous to Ronald Reagan's in 1980, when voters were even more intensely dissatisfied than they now are. There were hostages in Iran and stagflation's "misery index" (the sum of the inflation and unemployment rates) was 21.98. By August 1979, 84% of Americans said the country...